Fig. 3: IL-6 in the EVs of MMA-treated fibroblasts mediates pro-aggressive STAT-3 and TGFβ signaling in tumor cells.
a Volcano plots showing protein level distribution from proteomics analysis comparing the compositions of EVs isolated from vehicle- or MMA-treated MRC-5 fibroblasts (n = 3 independent experiments, two-sided paired t-test). b Immunoblots showing JAK2-STAT3 signaling and TGFβ signaling after 3 h of EV treatment in A549 cells. c Immunoblots measuring signal activation in A549 cells pre-treated with vehicle, TGFβR inhibitor SB431542 or JAK inhibitor cryptotanshinone for 30 min, then treated with EVs from MRC-5 fibroblasts for 3 h. d–f Pro-aggressive properties of A549 cells treated with EVsveh-MRC5 or EVsMMA-MRC5 with or without the TGFβR inhibitor SB431542 or the JAK inhibitor cryptotanshinone for 4 days, evaluated by immunoblots measuring EMT marker expression (d), carboplatin resistance assay (e; n = 3 independent experiments, mean ± SEM, two-way ANOVA), and invasion and migration transwell assays (f; red scale bar indicates 100\({{{{{\rm{\mu }}}}}}\)M, n = 3 independent experiments, mean ± SEM, two-sided paired t-test). g Immunoblots measuring signal activation in A549 cells with shGFP or shIL-6R knockdown (#1 and #2) and treated with EVsveh-MRC5 or EVsMMA-MRC5 for 3 h. h–j Pro-aggressive properties of A549 cells treated with of EVsveh-MRC5 or EVsMMA-MRC5 with shGFP or shIL-6R knockdown for 5 days, evaluated by immunoblots measuring EMT marker expression (h), carboplatin resistance assay (i; n = 3 independent experiments, mean ± SEM, two-way ANOVA), and invasion and migration transwell assays (j; red scale bar indicates 100\({{{{{\rm{\mu }}}}}}\)M, n = 3 independent experiments, mean ± SEM, two-sided paired t-test).
